Piped IO : PipedInputStream « File « Java Tutorial

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2. File
3. PipedInputStream

import java.io.IOException;
import java.io.PipedInputStream;
import java.io.PipedOutputStream;

class PipedIOApp {
  public static void main(String args[]) {
    Thread thread1 = new Thread(new PipeOutput("Producer"));
    Thread thread2 = new Thread(new PipeInput("Consumer"));
    thread1.start();
    thread2.start();
    boolean thread1IsAlive = true;
    boolean thread2IsAlive = true;
    do {
      if (thread1IsAlive && !thread1.isAlive()) {
        thread1IsAlive = false;
      }
      if (thread2IsAlive && !thread2.isAlive()) {
        thread2IsAlive = false;
      }
    } while (thread1IsAlive || thread2IsAlive);
  }
}

class PipeIO {
  static PipedOutputStream outputPipe = new PipedOutputStream();

  static PipedInputStream inputPipe = new PipedInputStream();
  static {
    try {
      outputPipe.connect(inputPipe);
    } catch (IOException ex) {
      System.out.println("IOException in static initializer");
    }
  }

  String name;

  public PipeIO(String id) {
    name = id;
  }
}

class PipeOutput extends PipeIO implements Runnable {
  public PipeOutput(String id) {
    super(id);
  }

  public void run() {
    String s = "This is a test.";
    try {
      for (int i = 0; i < s.length(); ++i) {
        outputPipe.write(s.charAt(i));
        System.out.println(name + " wrote " + s.charAt(i));
      }
      outputPipe.write('!');
    } catch (IOException ex) {
      System.out.println("IOException in PipeOutput");
    }
  }
}

class PipeInput extends PipeIO implements Runnable {
  public PipeInput(String id) {
    super(id);
  }

  public void run() {
    boolean eof = false;
    try {
      while (!eof) {
        int inChar = inputPipe.read();
        if (inChar != -1) {
          char ch = (char) inChar;
          if (ch == '!') {
            eof = true;
            break;
          } else
            System.out.println(name + " read " + ch);
        }
      }
    } catch (IOException ex) {
      System.out.println("IOException in PipeOutput");
    }
  }
}